When Transport Minister Michael Wood this month announced a consultation on New Zealand’s biggest long-term planned infrastructure project, experts began to ponder what a possible $15 billion could buy.
Could the Waitematā second harbour crossing be another bridge with trains, buses, walking, cycling, freight plus extra private vehicle capacity?
Or could it be a new tunnel or tunnels?
If it’s a tunnel or tunnels, could those be two-level, relatively narrow and separated in each direction creating divided cavities?
Or could the structure or structures be a much wider multi-level configuration? And if the former is the case, how is the long-term future safeguarded?
Transport and urban design expert Matt Lowrie and spatial planner Ben Ross agree on what they don’t like and which they both believe is being quietly talked about right now by the Crown agency.
That’s two separate two-level tunnels.
Lowrie posted an image of that on the Greater Auckland website this month, saying it was an option the Crown agency had previously supported and which he believes could be discussed as a possibility by Waka Kotahi NZ Transport Agency.
The agency is staying mum on whether it favours a tunnel or a bridge.
“No decision has been made yet,” a spokesperson told the Herald.
“The recently appointed alliance is commencing an indicative business case which will explore all modes of transport for a package of improvements confirming the timing, form, and route of future new connections and how we best use our existing infrastructure, with a recommendation expected to be delivered by mid-2023. This work also includes public consultation.”
Sent the image Lowrie and Ross think is the most likely, she said: “We won’t be able to confirm any of the above until this work is complete.”
More liberal pro-public transport/cycling/walking camps, which Lowrie and Ross belong to, would prefer a bridge with less of a focus on private vehicles but offering more alternative means of transport.
“The perfect solution is a two-lane bus bridge that can be retrofitted for light rail later on,” Ross said.
That could have walking and cycling paths too, all for 10 per cent of a tunnel’s cost.
The estimated cost of an Auckland harbour crossing by tunnel, as promoted by Finance Minister Grant Robertson, could be $15b, the Herald has previously reported.
Wood this month said Aucklanders would be asked to have their say on “one of the most significant city-shaping projects for Tāmaki Makaurau in coming decades: the Waitematā Harbour crossing”.
He said the Government was upgrading New Zealand’s transport infrastructure to future-proof the system for future generations, securing New Zealand’s economy and supporting the country’s biggest city.
As part of the development of options for future transport connections across the Waitematā Harbour, the project team wanted to understand Aucklanders’ aspirations for a future crossing.
Lowrie said the Crown agency probably favoured a two-level tunnel.
“There remains a strong push by Waka Kotahi for a combined tunnel solution, such as this shown on past work,” he said showing the image captioned AWHC - tunnel cross-section.
“While it might seem good at first glance, the reality is that both road and public transport crossings get compromised by being lumped together. Separating them allows for infrastructure to be optimised for the modes they’re serving and staged when they’re actually needed,” he said.
Wood said a preferred option of harbour crossing would be chosen by the middle of next year, with a view to breaking ground on the project by the end of this decade, significantly earlier than the previous timeline for the project which would have pushed it into the 2040s.
Whatever is chosen will be one of the most complicated and expensive infrastructure projects attempted in New Zealand, perhaps costing $10b.
The completed project will involve the existing bridge plus a new bridge or tunnel and provide space for walking, cycling, public transport, freight and private vehicles.
It will have to contend with Auckland’s growing pains now and in future - including whatever decision is made over the future of Auckland’s port.
A business case prepared by Waka Kotahi NZ Transport Agency costed a tunnel option at about $10b. It had a relatively low benefit-cost ratio of 0.2 – an 80 cent loss on every dollar spent on the tunnel.
Ross of Colab & Associates said the image above was one he favoured.
That showed a bridge, not a tunnel, tracking beside the existing Auckland Harbour Bridge.
“It is from NZTA themselves. It straddles State Highway 1, making land use minimal. On the northern side, it would be 5m higher than the existing State Highway 1, creating a de facto sea wall to stop the motorway getting flooded,” Ross said.
The agency and partners said it, Auckland Council, Auckland Transport and Ngā Iwi Mana Whenua o Tāmaki Makaurau had started a crucial phase in planning Aotearoa New Zealand’s most significant city-shaping project, Waitematā Harbour Connections.
“Waitematā Harbour Connections will provide for a fully multi-modal solution for people wanting to walk, cycle, transport freight, drive, take the bus or travel by light rail across the Waitematā Harbour, connecting people to transport options across the region,” the agency said.
“Planning work is under way to investigate what new infrastructure is needed to cater for these modes, where it will go, and how we make the best use of our existing infrastructure including the Auckland Harbour Bridge.”
An event on the proposal is planned for November 27 at the Highbury Night Market, another on December 3 at the I Love Takapuna Christmas carnival and one on December 11 at Grey Lynn Farmers Market.
“A well-connected, sustainable, resilient and reliable transport system gives people more choices, helps tackle harmful pollution, encourages quality growth, and supports a productive economy,” the agency said.
“Waitematā Harbour Connections is a key part in Tāmaki Makaurau Auckland’s rapid transit journey, unlocking even more benefits for the region by using rapid transit to move people across the harbour.
“A new light rail connection will supplement the existing Northern Busway, integrating effectively with the wider public transport network to keep up with growing passenger demand,” the Crown agency added.
This phase of technical work will be determined next year. Completion of the business case is expected in early 2024.
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